Roller arrangement, in particular for paper folding, creasing and like machines

ABSTRACT

The present invention concerns a roller arrangement, in particular for use in connection with paper treating machines and more specifically with paper folding, creasing and like machines, in which one or several pairs of rollers are employed and operated for conveying and/or folding a pile of sheets of paper or other cellulosic materials having different thicknesses with respect to each other and arranged parallel in axial direction to each other. Such sheets of material are operatively connected and subjected to common drive means, each pair of feed and sheet conveyor rollers including at least one hard surfaced or steel roller and a further roller for cooperation with the latter carrying a shell or jacket of friction material surrounding its core and presenting a rubbing or friction surface.

United States Patent 1191 Lehmann 5] Jan. 29, 1974 [75] Inventor: Werner Lehmann,Gutach,

Germany [73] Assignee: Firma Mathias Bauerle GmbH,

Georgen, Switzerland 22 Filed: Dec. 29, 1971 21 Appl. No.: 213,649

[30] Foreign Application Priority Data 10/1971 Moos 271/52 OTHER PUBLICATIONS IBM Technical Disclosure Bulletin Primary Examiner-Richard E. Aegerter Attorney, Agent, or Firm-John J. McGlew et a1.

[ ABSTRACT The present invention concerns a roller arrangement, in particular for use in connection with paper treating machines and more specifically with paper folding, creasing and like machines, in which one or several pairs of rollers are employed and operated for conveying and/or folding a pile of sheets of paper or other cellulosic materials having different thicknesses with respect to each other and arranged parallel in axial direction to each other. Such sheets of material are operatively connected and subjected to common drive means, each pair of feed and sheet conveyor rollers including at least one hard surfaced or steel roller and a further roller for cooperation with the latter carrying a shell or jacket of friction material surrounding its core and presenting a rubbing or friction surface.

2 Claims, 5 Drawing Figures PATENTED JAN 291974 SHEET 1 UF 2 PATENTEB JAN 2 9 I974 SHEET 2 BF 2 ROLLER ARRANGEMENT, IN PARTICULAR FOR PAPER FOLDING, CREASING AND LIKE MACHINES BACKGROUND OF THE INVENTION Field of the Invention In heretofore known roller arrangements of the ma chinery of the aforesaid type the frictional rollers with their coatings generally possess thin-walled elastic coverings having a relatively high degree of hardness, somewhat similar to rollers for use in the typewriters which after being applied to the metal core of the roller must be finish-ground or otherwise prepared along the entire length of the roller in order to obtain an even, continuous and constant diameter of the respective roller.

The respective high degree of hardness of the rubber covering becomes necessary, in order to reduce to a great degree the wear-off and the abrasive effect even after a relatively long time of operation. The disadvantage which emanates from such cases is that at least one roller of cooperable roller pairs arranged in opposite relation to each other must be either spring-supported in radial direction or must be adjustably journalled in order to be able to convey and/or fold sheets of paper or such other materials with variable thicknesses. Radially movable bearing structures require however, that always one roller of each pair of rollers at relatively great expense, replacement parts, assembly or mounting skill and workmanship and adjusting work, which contribute to a highly undesirable maintenance of such machine, which led to quite difficult and cumbersome construction. Also, the exchange of single rollers which were worn or had become unsuitable for a new one, has encountered many difficulties in heretofore known roller assemblies.

SUMMARY OF THE INVENTION The present invention overcomes these and other objections and fullfills the task to create a novel roller arrangement of the aforesaid type, which leads to a great simplification and reduction of expense in regard of a proposed employment of rollers which last a longer operational lifetime and are easier to maintain than heretofore known pairs of roller structures.

The solution of the problem with which the invention deals, is characterized in that the cooperable rollers of eachpair, when arranged in pairwise formation assume a definite and rigid distance from center to center of each other, and in a considerably simplified manner each roller of a pair of rollers possessing also a frictional shell material made from specially prepared, foamed polyurethane material having a specific or volumetric weight of approximately 0.4 p/cm.

It is therefore an important object of the invention to provide means resulting not only in a considerably simplified roller journal structure which is conditioned on the predetermined rigid axial distance between the rollers of each pair, but also due to highly improved transporting, feeding or conveying capability of each pair of cooperable steel and frictional rollers, due to their highly desirable frictional characteristics and inherent resistance to wear which are the cause for a much longer life of the novel frictional rollers.

It is another object of the invention to provide means facilitating the adjustment of the axial distance between two cooperable rollers of the aforesaid type by completely eliminating such adjustment when sheet material of different thicknesses are simultaneously subjected to an operative working system between the mentioned pairs of rollers.

It is still another object of the invention to provide means leading to a highly desirable function of such roller arrangement in an efficacious machine buildup which is considerably simplified and in a case of exchange requirement of rollers do not necessitate a precision-like manipulation by the operator.

It is a further important feature of the present invention to provide means conducive to keep the distance between steel roller and frictional roller at the most equal to the sum of their respective radii.

During heretofore known roller constructions used for at least heavier sheet material between two respective cooperable rollers a uniformly spaced distance along the entire length of the rollers had to be adjusted, while when working with very thin piled sheets of paper considerable difficulties were encountered to feed such latter sheets through the same machine at a changed uniform gap or elongated passage way which was difficult to achieve between their rollers; it was practically inconvenient to handle heavy, as well as very thin sheets of paper and like material without always preadjusting the respective axial distance between the rollers.

According to this invention the rubbing shell for one of the rollers or frictional material may be polyurethane or a similar substance which on one hand offers sufficient friction with a surface which is rather smooth, constant throughout or may have a very fine porous circumferential surface. In the latter case, it is possible to add to or impregnate such polyurethane substance with anti-static liquid composition known per se, in order to avoid any static charge during passage of papers and to thus bring about an electric neutralization of environmental atmosphere.

In furtherance of the present invention provision is also made that the journals or bearing bushings of the rollers fit relatively loosely in respective bores of bearing plates and are commonly secured in position through holding plate means, which are operatively connected to the bearing plate.

It is still another object of the invention to provide means implementing an extremely simplified and rather price-reduced assembly of the rollers in a most economical way, the exchangeability of single rollers e.g. for its removal from the respective bearing bushing requiring only the release from one holding or support plate. The bearing bushings can be readily and easily taken off for removal from the bearing plates and can be again thereafter reinstalled or mounted thereon.

It is also an advantageous feature of the invention to provide means rendering it possible to arrange between the bearing bushings and holder plates respective elastic pressure rings, which afford a substantially uniform and even distribution of pressure from the holding plates onto the individual bearing bushings.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference should be had to the accompanying drawings .and descriptive matter in which there is illustrated a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows schematically and in section a folding machine and arrangement of its roller pairs pursuant to the invention;

FIGS. 2 and 3 illustrate respective, sectional views of one pair of rollers in the stage of feeding or transporting sheet material of different thicknesses;

FIG. 4-is a partial sectional view taken along two cooperable rollers equipped with a bearing construction made in accordance with the invention;

FIG. 5 shows a side elevation of the support plate with the bearing bushings and their accessory parts.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring in greater details to the accompanying drawings, there is disclosed a folding machine schematically shown in FIG. 1 which machine comprises two rotatable roller pairs 3, 4 which cooperate with each other and are -journalled on lateral support plates 2, a sorting device 5 for detaching successively single paper sheets from a pile thereof, a deposit table 6 and two folding pocket-shaped means 7 and 8 and a sheet collector table 9.

The single paper sheet sorting device 5 consists of a stationary and adjustable disk 10 with a surface made from corundum or like fine and small particles containing material which disk is eccentrically joumalled and thus adjustable in its position and further of a transporting or single sheet conveyor roller 11 which has a metallic or like hard core 12 around which is located a cover layer of polyurethane in foam formation and of a predetermined thickness. The'said two roller pairs 3 and 4 consist each of a finish-ground steel roller 13 and 14, respectively, whereas their cooperable friction rollers 15, 16 with their hard cores have a covering shell made of polyurethane, held thereon. The axial distances between said roller pairs 3 and 4 and, more specifically, stated between the aforesaid frictional roller and the steel roller 13, as well as between the steel roller 13 and its further cooperable friction roller 16, and also between the latter roller and steel roller 14 are fixed, rigid and consequently unalterable. Such roller distance is definitely somewhat smaller (.2 to 1 mm) than the sum of the radii of two cooperable adjacent rollers.

The friction rollers 15 and 16 each possess a respective core 17 and 18 of rigid material, especially metal, and a friction shell 19 and 20, the wall thickness of which corresponds approximately to the radius of the respective core and consists of polyurethane having at least a specific weight of 0.4 p/cm As can be seen in FIGS. 2 and 3, these pairs of rollers are capable of handling and sorting relatively thin sheets 21 of paper and the like, having a thickness of approximately 0.5 mm, but also respective considerably thicker or heavier sheets 22 (FIG. 3) over the entire length of the roller without any objections to afford uniformly the desired feed and transport of the sheets, while the shell forming layer of polyurethane remains sufficiently yieldable or elastic to let pass successively or simultaneously not only relatively thick, but also heavier or thicker paper and like material. During the cooperation of the rollers, the metal roller 13 serves as a counter bearing and can be driven without any disturbance. The material, such as polyurethane of the indicated specific weight is not only sufficiently elastic, but fullfills also the task of being greatly resistant to wear and offers sufficient abrasive resistance during use so that these types of rollers will have a sufficient operational life.

The surface of the frictional layers 19 and 20 can be cast and forrns,when manufactured from polyurethane, an outer skin surface which is smooth and constant. However, it is also possible that the top surface is kept in a finely porous state which renders the possibility of impregnating one or both frictional layers with a known anti-static liquid composition in order to electrically neutralize any possibly charged paper sheets during their passage through such sets of rollers.

In FIG. 4, there is disclosed an embodiment of a pair of rollers 3 which are arranged in simple and rigid bearing conditions. In one of the two lateral plates 2 are loosely inserted and located at corresponding distances respective bearing bushings 25 and 26 in precision bores 23 and 24. In the bearing bushings 25 and 26 are journalled for rotatable movement the extending shaft ends 27 and 28 which serve as trunnions for the reduced cylindrical ends. These bushings are rotatably joumalled by means of needles 29, 30 and are also secured in position by means of slidable disks 31 and 32 in axial direction thereof. The bearing bushings 25 and 26 are retained in position also like the bearing bushings of the pairs of journals 4 (not shown) by means of a holder plate 33. This holder plate 33 is attached by means of screws 34, 35, 36 to the wall plate 2. In order to compensate for any tolerances resulting from its manufacturing process, as well as from any bending actions, there are arranged rubber rings 37, 38, which are interposed between the bearing bushins 25 and 26 and the holder plate 33. However, other yieldable elements (not shown) similar to spring washers or disks may be employed instead of said pressure rubber rings.

Outside of the holder plate 33, there are arranged on shaft ends 27 and 28 respective gear wheels 39 and 40 which are in mesh with each other and serve to drive the respective rollers 15, 13, 16 and 14 so that they run in opposite directions to each other.

Due to a very simplified construction and arrangement of the bearing bushings 25 and 26 on support plate 2 by means of holder plate 33, which is common to all bearing bushings, the removal of one or of all bearing bushings as the case may be, may be had or the exchange or replacement of one roller or the entire roller structure, is quite simple as there are only three screws 34, 35, and 36 to be loosened or released in order to take off holder plate 33. As may be realized from FIG. 4, there is shown a set of gears 39 and 40 which mesh with respective other gears (not shown), all these gears being removable from the respective shaft ends 27, 28 of the rollers, so that it suffices when only holder plate 33 will be taken off.

Function and operation of the paper and like folding machine, as schematically shown in FIG. 1, are well known per se. By means of single sheet sorting and directing device 5, the individual paper sheets are singly and succesively fed and delivered to a deposit table 6 by means of a transporting roller 11 and are then guided for action between roller pair 4. Thence, the respective paper sheet slides first into a pocket-shaped folding appliance 7 until it comes into contact with a respective end abutment therein which folds over the frontal edge of the sheet at 7 so that a first fold or crease section is formed therein. This first folded sheet end section is then deleivered and fed to run between rollers 13 and 16 and passes from the same in the direction of another pocket-shaped folding appliance 8 for folding therein the opposite paper sheet end. As soon as the first-shaped folded paper reaches the bottom or abutment end of the pocket-shaped appliance 8 (which can be angularly adjusted as indicated by the arrows in FIG. 1), then a second folded end section is formed, which is passed thereafter through roller pair 3. Thus, the two folded or creased end sections of each paper sheet are transported onto the top of appliance 7, which forms collector table 9, where the two-foldsheets are stored and piled up for any intended purpose.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be un derstood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

1. A roller arrangement, in particular, for paper folding or creasing machines which possesses at least one roller pair for conveying, distributing and/or folding singular sheets of paper and similar cellulosic material having various thicknesses and which are arranged in parallel relation and axially aligned to each other, wherein a common drive actuates pairs of rollers, each pair of which possesses at least one hard-surface steel roller and at least one cooperable roller with a frictional layer; characterized in that the rollers cooperate with respective pair-wise arranged rollers, which provide a predetermined rigid axial distance from each other, one roller of each roller pair being provided with a frictional yieldable shell of polyurethane having a specific weight of approximately 0.4 p/cm", a bearing plate having a plurality of bearing bushing receiving bores, a bearing bushing for each of said rollers mounted in respective bores of said bearing plate, said bearing bushings fitting loosely within the receiving bores, a common holder plate spaced from said bearing plate and holding and securing said bushings in place in said bearing plates, and resilient shock absorbing means disposed between said holder plate and said bearing bushings.

2. A roller arrangement, in particular, for paper folding or creasing machines which possesses at least one roller pair for conveying, distributing and/or folding singular sheets of paper and similar cellulosic material having various thicknesses and which are arranged in parallel relation and axially aligned to each other, wherein a common drive actuates pairs of rollers, each pair of which possesses at least one hard-surface steel roller and at least one cooperable roller with a frictional layer; characterized in that the rollers cooperate with respective pair-wise arranged rollers, which provide a predetermined rigid axial distance from each other, one roller of each roller pair being provided with a frictional yieldable shell of polyurethane having a specific weight of approximately 0.4 p/cm a bearing plate having a plurality of bearing bushing receiving bores, a bearing bushing for each of said rollers mounted in respective bores of said bearing plate, said rollers having reduced shaft portions journalled in said bearing bushings, each shaft portion having a drive gear affixed thereto which is in meshing engagement with the drive gear affixed to the other roller, a holding plate spaced outwardly from said bearing plate, securing bolts securing said holding plate to said bearing plate and elastic material disposed between said bearing bushings and said holding plate. 

1. A roller arrangement, in particular, for paper folding or creasing machines which possesses at least one roller pair for conveying, distributing and/or folding singular sheets of paper and similar cellulosic material having various thicknesses and which are arranged in parallel relation and axially aligned to each other, wherein a common drive actuates pairs of rollers, each pair of which possesses at least one hard-surface steel roller and at least one cooperable roller with a frictional layer; characterized in that the rollers cooperate with respective pair-wise arranged rollers, which provide a predetermined rigid axial distance from each other, one roller of each roller pair being provided with a frictional yieldable shell of polyurethane having a specific weight of approximately 0.4 p/cm3, a bearing plate having a plurality of bearing bushing receiving bores, a bearing bushing for each of said rollers mounted in respective bores of said bearing plate, said bearing bushings fitting loosely within the receiving bores, a common holder plate spaced from said bearing plate and holding and securing said bushings in place in said bearing plates, and resilient shock absorbing means disposed between said holder plate and said bearing bushings.
 2. A roller arrangement, in particular, for paper folding or creasing machines which possesses at least one roller pair for conveying, distributing and/or folding singular sheets of paper and similar cellulosic material having various thicknesses and which are arranged in parallel relation and axially aligned to each other, wherein a common drive actuates pairs of rollers, each pair of which possesses at least one hard-surface steel roller and at least one cooperable roller with a frictional layer; characterized in that the rollers cooperate with respective pair-wise arranged rollers, which provide a predetermined rigid axial distance from each other, one roller of each roller pair being provided with a frictional yieldable shell of polyurethane having a specific weight of approximately 0.4 p/cm3, a bearing plate having a plurality of bearing bushing receiving bores, a bearing bushing for each of said rollers mounted in respective bores of said bearing plate, said rollers having reduced shaft portions journalled in said bearing bushings, each shaft portion having a drive gear affixed thereto which is in meshing engagement with the drive gear affixed to the other roller, a holding plate spaced outwardly from said bearing plate, securing bolts securing said holding plate to said bearing plate and elastic material disposed between said bearing bushings and said holding plate. 